What sensor am i looking at???

Hey guys, I cant seem to find my haynes manual and Im not the most knowledgale with the 8s (Im a 4 banger enthusiast lol I know I know) I have a 95 350 tbi, can anyone tell me what sensor is located on the drivers side head between cyl 1 and 3? Mine is broken off. I dont think it is what is causing my bad sputtering and missfires under load, the engine will cut out completely momentarily. Its got 400kms on it and is gettin pretty damn tired but still runs perfect and doesnt burn a drop of oil except the forementioned problem. I still get 550-650kms per tank, just changed the fuel filter and will be doin the cap rotor wires n plugs later today.

OK thanks, I was thinkin it was the temp sensor...as for a fuel pressure problem Im not thinkin that myself. I had the slight sputter problem in the fall last year before I parked the truck for pretty much all winter (just had no money to drive) It would happen for 5-10 mins after a cold start and would be mostly noticable during rain or damp mornings. Its just gotten progressivly worst and now does it all the time, only under load though.